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There is no facility in rails for handling authentication. You need to
either write your
own or use one of the many plugins out there (which generally still
require some
modification to work in your app). Examples are LoginGenerator,
SaltedHashLoginGenerator,
ModelSecurity, ActiveRBAC, acts_as_autheticated, acts_as_acl,
UserEngine, etc.
b

I recommend Rails Recipes by Chad Fowler. The current beta book as
two recipes on login and authentication schemes. You'll not only get
the login implementation that fits your application, but you'll also
have the benefit of understanding what's going on. Plus, you'll get
60 some odd additional recipes all for the same prices. (They might
even throw in a keychain or something.) :)
http://www.pragprog.com
Michael

Sure, you can get the pdf right here:
http://www.pragmaticprogrammer.com/titles/fr_rr/index.html
If you just want the pdf then just pick that, otherwise you can get
the combo pack, which gives you the pdf now and the hardcopy book when
it's released. It's a real savings to get the combo pack, plus I like
having a book around. Sometimes there's just not enough screen real
estate.
Good luck.
Michael